Fetal Growth Restriction (FGR, IUGR) | Types, Causes, TORCH Infections, Diagnosis, Treatment

Summary

This lesson discusses fetal growth restriction (FGR), also known as intrauterine growth restriction (IUGR), which refers to a fetus not growing to its genetic potential. The video outlines the causes of FGR, including maternal, placental, and fetal factors. It explores the two types of FGR: symmetric and asymmetric, along with their clinical features and associated risks. Diagnosis is primarily through ultrasonography, and treatment focuses on monitoring and managing complications, with early delivery sometimes required. The video highlights preventive measures and the importance of maximizing gestational age to reduce complications.

Takeaways

• 😀 Fetal growth restriction (FGR), also known as intrauterine growth restriction (IUGR), occurs when a fetus does not grow to its genetic potential, often leading to a birth weight less than the 10th percentile for gestational age.
• 😀 FGR affects 3-7% of pregnancies, with higher rates in developing countries and specific regions, such as some Asian countries.
• 😀 FGR can be caused by three main factors: maternal causes (e.g., malnutrition, smoking, substance abuse), placental causes (e.g., insufficiency, preeclampsia), and fetal causes (e.g., multiple gestations, congenital disorders, infections).
• 😀 The TORCH infections (Toxoplasmosis, Other infections like Syphilis, Rubella, Cytomegalovirus, and Herpes Simplex Virus) are key contributors to fetal growth restriction.
• 😀 There are two types of FGR: symmetric (Type 1) and asymmetric (Type 2). Symmetric occurs early in gestation, with both head and abdomen being affected, while asymmetric occurs later with a higher head-to-abdomen ratio due to placental insufficiency.
• 😀 Clinical signs of FGR may include certain physical features, such as smooth philtrum and small eye openings in cases of fetal alcohol syndrome, or overlapping fingers in Trisomy 18.
• 😀 FGR is associated with serious risks including increased fetal mortality, labor complications, and higher likelihood of needing a C-section or premature delivery.
• 😀 Long-term complications of FGR may include developmental delays, cognitive issues, and an increased risk of conditions such as metabolic syndrome, type 2 diabetes, ischemic heart disease, and psychological disorders.
• 😀 Diagnosis of FGR is primarily done through ultrasonography, using measurements such as estimated fetal weight and abdominal circumference below the 10th percentile, along with monitoring amniotic fluid levels.
• 😀 Treatment for FGR aims to maximize gestational age to reduce complications. Interventions may include antenatal steroids for lung maturation and magnesium sulfate for neuroprotection in cases of premature delivery.

Q & A

What is fetal growth restriction (FGR)?

Fetal growth restriction (FGR), also known as intrauterine growth restriction (IUGR), is an obstetrical condition where the fetus does not grow to its genetic potential. It is defined as a fetal weight below the 10th percentile for gestational age or a full-term infant weighing less than 2500 grams.

How does fetal growth restriction differ from being small for gestational age (SGA)?

Fetal growth restriction is different from being small for gestational age because FGR refers to a fetus not reaching its genetic growth potential due to external factors, whereas SGA refers to a fetus that is smaller but still growing within its genetic potential, which can be normal for some individuals.

What are the common causes of fetal growth restriction?

The causes of fetal growth restriction are categorized into maternal, placental, and fetal factors. Maternal causes include malnutrition, smoking, substance abuse, and diabetes. Placental causes involve issues like placental insufficiency and preeclampsia. Fetal causes include multiple gestation, congenital disorders, and infections like toxoplasmosis and cytomegalovirus.

What is the brain sparing effect in fetal growth restriction?

The brain sparing effect refers to the body’s mechanism of prioritizing blood flow and nutrients to vital organs such as the brain, heart, adrenal glands, and placenta in response to reduced gas exchange or nutrient delivery. This can result in the head and brain developing more normally while the rest of the body grows less.

What are the two types of fetal growth restriction?

The two types of fetal growth restriction are symmetric (Type 1) and asymmetric (Type 2). Symmetric FGR occurs early in gestation and affects the entire body equally, including both the head and abdomen. Asymmetric FGR occurs later in gestation, typically in the second or third trimester, and primarily affects the abdomen while sparing the head, resulting in a higher head-to-abdomen ratio.

What are the risks and complications associated with fetal growth restriction?

Fetal growth restriction can lead to various risks, including fetal mortality, labor complications, increased likelihood of a C-section, and prematurity. There is also an increased risk of meconium aspiration, electrolyte imbalances, hypoglycemia, polycythemia, necrotizing enterocolitis, and renal failure. Long-term risks include developmental delays, metabolic syndrome, obesity, and psychological impairments.

How is fetal growth restriction diagnosed?

Fetal growth restriction is commonly diagnosed through ultrasonography, which includes serial measurements of fetal weight, abdominal circumference, and head circumference. Amniotic fluid volume is also assessed, with a lower than normal amniotic fluid index suggesting growth restriction. Doppler studies of the uterine and umbilical arteries are also used for diagnosis.

What is the role of ultrasonography in diagnosing fetal growth restriction?

Ultrasonography plays a critical role in diagnosing fetal growth restriction by providing estimated fetal weight, head circumference, abdominal circumference, and femur length. It helps identify fetuses that are smaller than the 10th percentile for gestational age, allowing for the classification into moderate or severe cases.

What treatment options are available for fetal growth restriction?

There is no direct treatment for fetal growth restriction. The goal is to maximize gestational age and manage complications. If fetal growth restriction is diagnosed, frequent monitoring using Doppler studies and biophysical profiles is essential. In cases of premature delivery, antenatal steroids and magnesium sulfate may be administered to support lung maturation and neural protection.

What preventive measures can be taken to reduce the risk of fetal growth restriction?

Preventive measures include cessation of alcohol, smoking, and substance use, improving nutrition, and reducing the risk of TORCH infections. Regular prenatal care and monitoring for conditions like hypertension and diabetes are also important for reducing the likelihood of fetal growth restriction.